It’s hard to look at Sebastião Salgado’s epic photographs of indigenous tribesmen, wild animals, and remote landscapes without mixed feelings of awe and sadness. Forming the backbone of a current exhibition at Sundaram Tagore Gallery in Hong Kong, the 70-year-old Brazilian photographer’s “Genesis” series tells a sweeping story of our planet as it teeters on the edge of decline.

Salgado’s strength lies in his slow, involved process—he devoted eight years to this series, spending days on end living with his subjects in various corners of the world. The black-and-white prints on display alternate between individuals in unspoiled natural environments— Zo’é women bathing in the Brazilian state of Para and a lone man praying in the dunes of the Sahara desert—to concentrated portraits against clean backdrops.

While Salgado sets up makeshift studios on his travels, there is no trace of the ethnographic or egocentric in these images. It is an open, collaborative process resulting in photographs with probing intimacy: “I don’t pose anyone. I say come and do what you want,” Salgado said recently in an interview on the occasion of his new show. He gives the example of a shaman in West Sumatra who suggested he be photographed while creating a filter to make sago using narrow leaves. Wearing a delicate headdress fashioned with a leaf and flowers, the man sits cross-legged with a serene expression on his face.

The scene contrasts sharply with the searing images from Salgado’s earlier series “Workers,” which hang in the same room. One photograph shows three coal miners against a bleak landscape in Bihar India. They stare into the camera lens, their turbans and faces covered in soot with only their eyes and lips clean. Their gazes confront the viewer with the uncomfortable reality that hundreds of laborers have suffered at the expense of supposed progress toward a modern world.

Salgado, who began his career as an economist, has long been drawn to humanistic themes. “We were activists, we studied Marxism… Labour was the power of everything,” he says. After years of witnessing horrific working conditions worldwide, however, Salgado was deeply disillusioned. The idea for “Genesis” was born as a means of reviving his optimism and celebrating a world left unscathed by mankind.

Among the most interesting parts of his journey reflected in this show is his close engagement with animals, ranging from a mammoth right whale in Argentina to a leopard, which he shot at nighttime in Namibia. “We had this lie that they tell us our whole lives that we are the only rational species. It’s not true,” insists Salgado. “If you respect the dignity, personality, the rationality of each species, you can survive with them.” Through large-scale prints with dramatic backlighting and monumental compositions, he conveys a vision of oneness; the creatures in his images possess the same gravitas as his human subjects.

At a time when our lives are oversaturated with images and the medium of photography has undergone seismic change, Salgado, like the remote subjects he captures, is part of a disappearing breed. While he describes his lengthy projects as a reflection of his interests, they are much more than an autobiographical journey. Viewed in the heart of the densely urban environment of Hong Kong, the works in this show appear almost surreal, jolting the viewer to pause and take stock. A sense of nostalgia and an archeological bent pervade his photographs as they commemorate a world that for many has already slipped out of reach.